The present invention relates to a vehicle operated by electric battery power comprising an electric traction motor, a chopper-controller for controlling the motor speed and a battery chargeable from a power source separate from the vehicle. The invention also relates to a device for charging the battery of such a vehicle.
Electric battery powered vehicles have normally to be charged regularly from a power source separate from the vehicle. This can be done either by parking the vehicle and charging the battery while it remains in the vehicle or by changing the battery for another fully charged battery. For heavy battery powered vehicles, i.e. loading vehicles, the battery capacity will usually not last for a full work shift which means that the vehicle or the battery must be exchanged before the end of the shift. This causes problems with working interruptions for changing the battery or also the economic disadvantage of having two vehicles instead of one.
One solution to that problem could be to provide the vehicle with a charging device located in the vehicle so as to enable charging of the battery also during short working interruptions, lunch breaks etc. In that way the operation time of the battery could be substantially prolonged without having undesirable breaks during the operation of the vehicle.
The object of this invention is thus to provide a battery operated vehicle which has a charging device integrated with the electrical system of the vehicle and especially to provide a vehicle of the above kind whose traction motor speed is controlled by a chopper-controller adapted in such a way as to make it possible to use it also for controlling the supply of charging energy to the battery. This purpose and others are achieved by providing a vehicle according to the accompanying claims.
The invention will now be further described in connection with the enclosed drawings.